import numpy as np
arr1d = np.array([1,2,3])
print(arr1d)
arr2d = np.array([[1,2,3],[4,5,6]])
print(arr2d)

print(np.array([1,2,3],dtype = np.float32))
print(np.linspace(1,20,5))
print(np.zeros((3,3)))
print(np.ones((3,3)))
print(np.arange(1,20,5))


date = np.array([[1,2,3],[4,5,6]])
float_date =date.astype(np.float32)
float_date.dtype
print(float_date)

float_date=np.array([1.2,2.9,3.5])
int_date=float_date.astype(np.int32)
int_date
print(int_date)

str_date =np.array(['1','2','3'])
int_date=str_date.astype(np.int64)
int_date
print(int_date)